Polypectomy device and method

ABSTRACT

A polypectomy device and method which includes a snare cable, a fixed jaw and a moveable jaw. The snare cable is routed through both the fixed jaw and the moveable jaw. The snare cable forms a hoop for encircling the polyp. Shortening the snare cable positions the jaws about the base of the polyp and further shortening the cable closes the jaws. The fixed jaw includes a heating element which cauterizes the base of the polyp. The closing of the jaws and the heating of the heating element cuts and seals the polyp.

This application is a continuation of U.S. application Ser. No.09/917,104 filed Jul. 27, 2001, now U.S. Pat. No. 6,616,659.

FIELD OF THE INVENTIONS

The invention relates general to medical devices, and more specificallyto devices for performing a polypectomy.

BACKGROUND OF THE INVENTIONS

Polyps are defined as any growth or mass protruding from a mucousmembrane. Polyps can occur wherever there is mucous membrane, namely, inthe nose, ears, mouth, lungs, heart, stomach, intestines, urinarybladder, uterus, and cervix. Most polyps are benign growths thateventually stop growing. But some of these polyps keep growing. Geneticmutations can transform them into cancerous tumors. As these canceroustumors grow larger, they continue growing and begin to burrow deeper anddeeper into the tissue supporting the polyp. In the final stages thecancer invades the blood and lymph systems and the malignant cells ofthe tumor spread to other organs. The problem is particularly severe,yet readily treated, in the colon. Colorectal cancer is the secondleading cause of death due to cancer in the United States. If the canceris detected and treated in its early stages, it can be cured more than90% of the time. Thus, early detection and removal of colorectal polyps,whether benign, pre-cancerous, or

cancerous, is highly effective in avoiding or treating colorectalcancer.

Polyps may be attached to a mucous membrane by a thin stalk or the polypmay have a broad base. A polyp that is attached by a thin stalk iscalled a pedunculated polyp and a polyp that is attached by a broad baseis called a sessile polyp. Various devices have been proposed forremoving polyps, especially pedunculated polyps, from the body. Forexample, Avellanet, Polypectomy Snare Instrument, U.S. Pat. No.6,015,415 (Jan. 18, 2000) teaches a polypectomy device using a snareloop connected to a power source to supply cautery current. The snareloop is used to capture the polyp and current is applied to the snareloop which cauterizes the polyp as the snare is closed tightly aroundthe polyp. McKeating, Polypectomy Instrument, U.S. Pat. No. 5,746,747(May 5, 1998) teaches a polypectomy device using grasping forceps tohold the polyp and a snare wire for cutting the polyp. Electricalcurrent is supplied to the snare wire to cut and cauterize the polypwhile the grasping forceps hold onto the body of the polyp. Nakao etal., Surgical Cauterization Snare with Ligating Suture, U.S. Pat. No.5,906,620 (May 25, 1999) teaches using two snare loops. The first loopcauterizes the polyp while the second loop acts as a suture for ligatingthe polyp. The second loop is left behind in the colon.

SUMMARY

The present polypectomy device and method effectively removes polypsfrom the body. The device includes a first jaw and a second jaw. One ofthe jaws includes a heating element for cauterizing the tissue of thepolyp. A snare cable is routed through each of the jaws. The snare cableforms a hoop for capturing the polyp. As the snare cable is pulledproximally it positions the jaws at the base or stalk of the polyp. Asthe snare cable is pulled further it closes the jaws. The closing of thejaws works in conjunction with a heating element to cut and seal thetissue between the jaws.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an overview of the polypectomy device inserted into the colonof a patient.

FIG. 2 is an overall side-view of the polypectomy device with a handle,an electrical connector, and a jaw assembly.

FIG. 3 is a close-up cross sectional view of the jaw assembly located onthe distal end of the polypectomy device.

FIG. 4 is an overview of the polypectomy device inserted into a sinus ofa patient with the snare wire encircling the base of the polyp.

FIG. 5 is a like view with the snare wire pulled proximally to align thejaws of the polypectomy device.

FIG. 6 is an overview of the polypectomy device inserted into the uterusof a patient with the snare wire encircling the base of the polyp.

DETAILED DESCRIPTION OF THE INVENTIONS

FIG. 1 shows an overview of the polypectomy device inserted into thecolon of a patient 1. The polypectomy device 2 includes an elongatedflexible catheter 3 extending out of the distal end of an endoscope 4.The distal end of the catheter includes a fixed jaw 5, a moveable jaw 6,and a snare cable 7. The snare cable may be operated to capture thepolyp 8 and as the length of the snare cable is shortened, the polyp isdrawn into the jaws and the moveable jaw is pulled toward the fixed jaw.The heating element 17 on the fixed jaw (See FIGS. 2 and 3) may beoperated to necrose the tissue trapped between the jaws. The combinationof heat and pressure causes the tissue to divide which severs the polypfrom the colon wall 9 of the colon 10.

FIG. 2 shows an overall side-view of the polypectomy device 2. Theproximal end of the device includes a two-wire electrical connector 12,and a handle 13. The two-wire electrical connector connects the catheter3 to an electrical power source (not shown). The handle includes a cabletrigger 14 and a fixed finger hold 15. The cable trigger may be operatedto pull the snare cable 7, which captures the polyp and operates themoveable jaw 6. Closing the jaw assembly and activating the power sourceto heat the heating element 17 cuts the polyp and seals the tissue.

FIG. 3 is a close-up cross sectional view of the distal end of thepolypectomy device. The snare cable 7, the fixed jaw 5 and the moveablejaw 6 extend out of the distal end of the catheter body 3. The fixed jawis attached to the catheter body, and the moveable jaw is operativelyconnected to the catheter body at a hinge 16. It should be noted thatwhile we have referred to a fixed jaw and a moveable jaw, both jaws maybe moveable. Both jaws may be hinged to the catheter, or otherwiserotatable relative to each other and secured to the catheter.

The fixed jaw 5 includes a heating element 17, an insulation tube 18,and a lumen 19. The moveable jaw 6 includes a hole 20 (through which thesnare cable passes) at its distal tip, a hinge 16 at its proximal end,and a silicone pad 21. A distal outlet 22 is formed by the lumen 19 ofthe fixed jaw extending completely through the fixed jaw. The fixed jawand the moveable jaw close together in a scissor-like movement. Thesurfaces of the fixed jaw and the moveable jaw that fit together are thegrasping faces. The silicone pad 21 of the moveable jaw is located alongthe grasping face of the moveable jaw and the portion of the insulationtube 18 facing the moveable jaw serves as the grasping face of the fixedjaw.

The fixed jaw and the moveable jaw can be composed of stainless steel orother suitable metal, plastic, or ceramic. The fixed jaw also includesan insulation tube that can be composed of polyamide, fluropolymer, or aPTFE/polyamide blend such as Xylan® (other insulative materials can beused). The insulation tube 18 isolates the heating element 17 from thestainless steel portion of the fixed jaw thereby preventing the heatingelement from heating the entire fixed jaw.

The heating element is composed of an electrically conductive material,such as nichrome, which is sufficiently resistive to heat upsignificantly when electricity is passed through it. The heating elementcan be approximately 1/10,000 nichrome wire having a length ofapproximately 10 mm. The power supply can generate approximately 3 to 30watts of power, and the heating element approximately 2 to 7 watts ofpower. Alternative forms of heating elements may be used, such asceramic heating elements, RF heating elements, and monopolar and bipolarheating elements. Additionally, heating elements may be placed on eitherjaw, or on both jaws.

The distal end of the snare cable 7 is fixed to the catheter body 3 andextends along the outside of the moveable jaw 6 through the hole 20 inthe distal tip of the moveable jaw (though it may be fixed, at itsterminus, to the distal tip of the moveable jaw). The cable then goesinto the distal outlet 22 of the fixed jaw 5, through the lumen 19 tothe cable trigger 14 located at the proximal end of the device. Thelumen 19 of the fixed jaw includes a friction liner 23. The frictionliner can be composed of nylon or Teflon®, which reduces the frictioncreated by the snare cable 7 moving through the lumen of the fixed jaw,thereby permitting the snare cable to be operated smoothly and easily.

The fixed jaw 5 is formed as a cylindrical tube and the moveable jaw 6is formed as a concave semicylindrical body that mates with the fixedjaw. The fixed jaw and the moveable jaw are fashioned similar to acurling iron for hair, which includes a cylindrical heated tube and amoveable semicylindrical jaw that fit together to curl hair. In thecurling iron art the fixed jaw is called the barrel and the moveable jawis called the clip, and they function in a similar manner as the fixedjaw and the moveable jaw in this device. Thus, by analogy, the fixed jawmay be referred to as a barrel, and the moveable jaw may be referred toas a clip.

The outer most layer of the catheter body is an insulated catheterjacket 24. Inside the catheter body are the electrical wire 25, thebraided conductor 26, the lumen, and the snare cable 7. The electricalwire is connected to the distal end of the heating element 17, which islocated on the grasping face of the fixed jaw, and supplies theelectrical current from the electric source to the heating element. Thecurrent flows from the electric power source into the two-wireelectrical connector 12 through the electrical wire 25 into the heatingelement 17. The current then flows from the heating element through theconductive crimp 27, located at the proximal end of the heating element,into the braided conductor 26 and back to the two-wire connector tocomplete the circuit. The braided conductor may be replaced with a wireif space permits.

In use, an endoscope is inserted into the patient's body to the areawhere the polyp is located. The endoscope is used to view inside thepatient's body and look for polyps. If a polyp is found the surgeoninserts the polypectomy catheter into the working lumen of theendoscope. The surgeon then moves the distal end of the catheter towardthe polyp and extends the snare cable to form a hoop which enables thesurgeon to capture the polyp. The surgeon manually rotates the cathetersuch that the snare cable hoop can be properly oriented and placed overthe polyp. The manual rotation of the catheter is accomplished byrotation of the handle.

Once the polyp is encompassed by the snare cable, the surgeon activatesthe cable trigger thereby drawing the snare cable proximally relative tothe catheter and closing the loop about the polyp. As the surgeon pullsthe snare cable, the fixed jaw and the moveable jaw are pulled intoplace on either side of the polyp. As the surgeon further shortens thesnare cable, it operates the moveable jaw to draw it toward the fixedjaw, thereby pulling the jaws together. The electrical power source isactivated, which heats the heating element located on the fixed jaw.Therefore, as the jaws are held closed, the heating element and the jawswork together to both cut and seal the tissue. The power source may beactivated by a footswitch (not shown), or it may be operated by a switchor button located on the catheter or the power source. It may also beactivated by a limit switch which is activated by the proximal movementof the cable trigger.

As discussed above, polyps form in mucous membrane, and mucous membranesexist in many areas of the body. Polyps can form in a patient's colon10. One way of looking for polyps in a patient's colon is a colonoscopy.During a colonoscopy the surgeon inserts an endoscope 4 into thepatient's colon through the patient's anus 28 (See FIG. 1). If a polyp 8is found, the surgeon inserts the polypectomy device 2 into the workinglumen of the endoscope and follows the procedure discussed above.

Similarly, as shown in FIG. 4, polyps formed in the nasal sinuses can beremoved with the device. A like procedure is followed. An endoscope 4 isinserted into the patient's nasal sinuses 29, through the patient'snostril 30. Once a polyp 8 is located, the polypectomy device 2 isinserted into the endoscope. The snare cable 7 extends to form a hoopwhich enables the surgeon to capture the polyp. Once the polyp isencompassed by the snare cable, the surgeon activates the cable trigger14 thereby drawing the snare cable proximally. As shown in FIG. 5, asthe surgeon pulls the snare cable proximally, the fixed jaw 5 and themoveable jaw 6 are pulled into place on either side of the polyp 8. Asthe surgeon further pulls the snare cable, it operates the moveable jawto draw it toward the fixed jaw, thereby mating the jaws together, or atleast bring the jaws into apposition with the polyp stalk caught betweenthem. With the activation of the moveable jaw, the electrical powersource is activated, which heats the heating element located on thefixed jaw. The power source is activated by a footswitch (not shown).Thus, as the jaws are held closed, the heating element and the jaws worktogether to both cut and seal the tissue.

As illustrated in FIG. 6, polyps in a patient's uterus can be removedwith the device. Again, a like procedure is followed. An endoscope 4 isinserted into the patient's uterus 31 through the vagina 32. If a polyp8 is found, the surgeon inserts the polypectomy device 2 into theworking lumen of the endoscope and follows the procedure discussedabove.

Similar procedures can be performed in other parts of the body wherepolyps or other abnormal tissue growth occur, and the examples of colonpolyps, sinus polyps, and uterine polyps illustrate the procedure whichcan readily be adapted to other conditions. Thus, while the preferredembodiments of the devices and methods have been described in referenceto the environment in which they were developed, they are merelyillustrative of the principles of the inventions. Other embodiments andconfigurations may be devised without departing from the spirit of theinventions and the scope of the appended claims.

1. A system for removing a polyp from the body of a patient, said systemcomprising: an endoscope suitable for performing an endoscopic procedureon the patient; and a device for removing polyps, said devicecomprising: a catheter having a proximal end and a distal end; a cabletrigger operatively connected to the proximal end of the catheter; apair of jaws extending out of the distal end of the catheter; a heatingelement disposed on at least one of the jaws and located between thepair of jaws; a snare cable without the heating element, said snarecable routed through the pair of jaws and operatively connected to thecable trigger; and a source of power operably connected to the heatingelement; wherein the device for removing polyps is sized and dimensionedfor insertion into the endoscope.
 2. The system of claim 1 wherein theheating element is selected from the group consisting of a nichrome wireheating element, a ceramic heating element, an RF heating element, amonopolar electrode heating element and a bipolar electrode heatingelement.
 3. The system of claim 1 wherein: the pair of jaws comprises afirst jaw and a second jaw; the second jaw is rotatable relative to thefirst jaw; and the snare cable is operatively connected to the secondjaw and runs from the second jaw to the first jaw and then to the cabletrigger.
 4. The system of claim 3 further comprising a silicone paddisposed on the grasping face of the second jaw.
 5. A method of removinga polyp from the body of a patient, said method comprising the steps of:providing a system for removing a polyp from the body of the patient,said system comprising: an endoscope suitable for performing anendoscopic procedure on the patient; and a device for removing polyps,said device comprising: a catheter having a proximal end and a distalend; a cable trigger operatively connected to the proximal end of thecatheter; a pair of jaws extending out of the distal end of thecatheter; a heating element disposed on at least one of the jaws andlocated between the pair of jaws; a snare cable routed through the pairof jaws and operatively connected to the cable without the heatingelement, said snare cable trigger; and a source of power operablyconnected to the heating element; wherein the device for removing polypsis sized and dimensioned for insertion into the endoscope; inserting theendoscope into the body of the patient and locating the polyp with theendoscope; inserting the device for removing polyps into the endoscopesuch that the distal end of the device for removing polyps is located inthe vicinity where the polyp is located; extending the snare cable toform a hoop sized and dimensioned to capture the polyp; manipulating thehoop to capture the polyp; activating the cable trigger to draw thesnare cable proximally relative to the catheter and to close the hooparound the polyp; pulling the snare cable proximally relative to thecatheter to draw the polyp into position between the pair of jaws and toclose the pair of jaws upon the polyp; and supplying heating power tothe heating element to sever the polyp from tissue surrounding thepolyp.
 6. A method of removing a polyp from the body of a patient, saidmethod comprising the steps of: providing a device for removing polyps,said device comprising: a catheter having a proximal end and a distalend; a cable trigger operatively connected to the proximal end of thecatheter; a pair of jaws extending out of the distal end of thecatheter; a heating element disposed on at least one of the jaws andlocated between the pair of jaws; a snare cable routed through the pairof jaws and operatively connected to the cable without the heatingelement, said snare cable trigger; and placing the distal end of thecatheter in the proximity of the polyp; pushing the snare cable distallyrelative to the catheter to open the pair of jaws relative to each otherand form a hoop of snare cable extending from the distal end of thecatheter; manipulating the hoop to engage the polyp; pulling the snarecable proximally relative to the catheter to draw the polyp intoposition between the pair of jaws and to close the pair of jaws upon thepolyp; and supplying heating power to the heating element to sever thepolyp from tissue surrounding the polyp.